draw_circleT_draw_circleDrawCircleDrawCircledraw_circle (算子)

名称

draw_circleT_draw_circleDrawCircleDrawCircledraw_circle — 交互式绘制圆。

签名

draw_circle( : : WindowHandle : Row, Column, Radius)

描述

draw_circledraw_circleDrawCircleDrawCircleDrawCircledraw_circle produces the parameter for a circle created interactive by the user in the window.

To create a circle you have to press the mouse button at the location which is used as the center of that circle. While keeping the mouse button pressed, the RadiusRadiusRadiusRadiusradiusradius's length can be modified through moving the mouse. After another mouse click in the created circle center you can move it. A clicking close to the circular arc you can modify the RadiusRadiusRadiusRadiusradiusradius of the circle. Pressing the right mouse button terminates the procedure. After terminating the procedure the circle is not visible in the window any longer.

注意

If used in a buffer window, mouse events have to be supplied by the application, while the draw operator must be run in another thread.

执行信息

多线程类型：可重入（与非独占算子并行运行）。
多线程作用域：全局（可从任何线程调用）。
未采用并行化处理。

参数

WindowHandleWindowHandleWindowHandleWindowHandlewindowHandlewindow_handle (输入控制) window → (handle)

窗口句柄。

RowRowRowRowrowrow (输出控制) circle.center.y → (real)

Barycenter's row index.

ColumnColumnColumnColumncolumncolumn (输出控制) circle.center.x → (real)

Barycenter's column index.

RadiusRadiusRadiusRadiusradiusradius (输出控制) circle.radius → (real)

Circle's radius.

示例（HDevelop）

read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)

示例（C）

read_image(&Image,"monkey");
draw_circle(WindowHandle,&Row,&Column,&Radius);
gen_circle(&Circle,Row,Column,Radius);
reduce_domain(Image,Circle,&GrayCircle);
disp_image(GrayCircle,WindowHandle);

示例（HDevelop）

read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)

示例（HDevelop）

read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)

示例（HDevelop）

read_image(Image,'monkey')
draw_circle(WindowHandle,Row,Column,Radius)
gen_circle(Circle,Row,Column,Radius)
reduce_domain(Image,Circle,ImageReduced)
invert_image (ImageReduced, ImageInvert)
dev_display (ImageInvert)

结果

draw_circledraw_circleDrawCircleDrawCircleDrawCircledraw_circle returns 2 ( H_MSG_TRUE) if the window is valid and the needed drawing mode (see set_insertset_insertSetInsertSetInsertSetInsertset_insert) is available。如有必要，则抛出异常。

可能的前趋

open_windowopen_windowOpenWindowOpenWindowOpenWindowopen_window

可能的后继

reduce_domainreduce_domainReduceDomainReduceDomainReduceDomainreduce_domain, disp_regiondisp_regionDispRegionDispRegionDispRegiondisp_region, set_coloredset_coloredSetColoredSetColoredSetColoredset_colored, set_line_widthset_line_widthSetLineWidthSetLineWidthSetLineWidthset_line_width, set_drawset_drawSetDrawSetDrawSetDrawset_draw, set_insertset_insertSetInsertSetInsertSetInsertset_insert

替代

draw_circle_moddraw_circle_modDrawCircleModDrawCircleModDrawCircleModdraw_circle_mod, draw_ellipsedraw_ellipseDrawEllipseDrawEllipseDrawEllipsedraw_ellipse, draw_regiondraw_regionDrawRegionDrawRegionDrawRegiondraw_region

另见

gen_circlegen_circleGenCircleGenCircleGenCirclegen_circle, draw_rectangle1draw_rectangle1DrawRectangle1DrawRectangle1DrawRectangle1draw_rectangle1, draw_rectangle2draw_rectangle2DrawRectangle2DrawRectangle2DrawRectangle2draw_rectangle2, draw_polygondraw_polygonDrawPolygonDrawPolygonDrawPolygondraw_polygon, set_insertset_insertSetInsertSetInsertSetInsertset_insert

模块

基础

算子